William s



(No Model.)

W. s. HADAWAY, Jr. & W. E. DAVIS. EHEOSTAT OR ELECTRIC HEATER.

Patented June 23, 1896.

Br flax W 4. M0625 ATTORNEYS.

AF DREW B CRAHAM.FNOTQ-UTNO WASNIEGTONJZC.

UNITED STATES PATENT OFFICE.

WILLIAM S. IIADAVAY, JR, OE NEV YORK, N. Y., AND \VILLIAM E. DAVIS, OFMALDEN, MASSACHUSETTS, ASSIGNORS TO THE CENTRAL ELECTRIC HEATINGCOMPANY, OF NE\V YORK, N. Y.

RHEOSTAT OR ELECTRIC HEATER.

SPECIFICATION forming part of Letters Patent No. 562,527, dated June 23,1896.

Application filed July 18,1895. Serial No. 556,329. (No model.)

To aZZ whom it may concern:

Be it known that we, TILLIAM S. HADA- WAY, J11, residing in the city,county, and State of New York, and WILLIAM E. DAVIS,

residing in the city of Malden, county of Middlesex, and Commonwealth ofMassachusetts, citizens of the United States, have invented certain newand useful Improvements in Rheostats or Electric Heaters, of which thefolo lowing is a full, true, and accurate description, reference beinghad to the accompanying drawings, wherein similar letters refer to likeparts in the several views.

The object of our invention is to produce an electric heater wherein theresistance-com ductor is combined with a suitable non-conducting core insuch a manner that if the conductor is broken the broken ends will besupported by the non-conducting core and shortcircuiting or groundingprevented, and the parts of the conductor will be instantaneously andwidely separated from each other.

Figure 1 is a plan view of one form of heater embodying our invention.Fi 2 is a longitudinal section of said heater. Fig. 3 is an enlargedview of one of the knobs, showing a portion of the spirally-woundconductor and itsnon-conducting core.

A is the resistance-conductor, preferably 0 made of spring metal woundin the form of a spiral.

B is a non-conducting core which supports the conductor, and sustainsits ends, if the same is broken, and prevents the short-circuiting orgrounding of the current which might otherwise occur.

The non-conducting core shown is an asbestos cord B, extendinglengthwise through and threaded within the coils of the conductor A. Asshown, the ends of the asbestos cord are attached to terminal-supports CC, Fig. 1, secured to the lower bar of a frame D, and the upper andlower bars E E of this frame are secured to the shorter angular bars FF,

forming a rectangular frame. Knobs G, of insulating material, aresecured to the longer bars E E, and are recessed to receive and hold thespiral conductor A.

The non-conducting core B and the resistance-coil surrounding it arewound back and forth across the frame and over the knobs G, and theframe is secured in an outer casing H, (onehalf of such casing onlybeing shown in the drawings.) This casing may be at tached to a wall bybolting it thereto, or be secured to the floor, or suspended underneatha seat or table by the legs I. Air circulates through the heater, whenin use, through the openings K in the casing.

The terminals of the resistance-conductor are soldered, or otherwisesecured, at L L to insulated conductors M M, which are connected withcontacts carried within a porcelain block N, fitted in the casing.

The resistance conductor is strung out upon the core to distend itscoils and keep it under a constant strain or tension, so that upon thebreaking of the conductor at any place the strain will cause theportions to instantaneously separate from each other, preventing theformation of an arc and the striking of the parts together, which mightfire near-by combustible material. The nonconducting core serves to holdthe conductor, whether broken or not, from falling against the casing,and prevents the ends of the conductor from dropping to the frame, byreason of the attachment of such ends to the core.

In the manufacture of the rheostat or heater we prefer to form theconductor into a coil before securing it to the core, and we prefer thatthe core shall lie loosely in the coil before the ends of the core areattached to it, so that, when such ends are attached, the tightening ofthe core will strain or distend the coil.

Having described our invention, what we claim is 1. In a rheostat orelectric heater, the com bination of insulated supports, and of aninsulated core stretched and suspended between said supports; with ahelical resistance strung upon said core and attached thereto so as tobe normally distended whereby, upon the breaking of any coil of thehelix, the broken 5 ends will be instantaneously separated by thecontraction of the portions of the helix; and means for connecting saidhelix in an electrical circuit, substantially as and for the purposedescribed. 10o

In a rheostat or electric heater, the comthe helix to the insulatedblock, substantially IO bination of the casing, the longitudinal bars asdescribed. on opposite sides thereof, and the insulated In witnesswhereof we have hereunto signed block carried by the casing; withinsulators our names this 16th day of July, 1895.

5 carried by the said bars, a non-conducting XVILLIAM S. IlADAlVAY, JR.

core passing from one insulator to another, 'WILLIAM E. DAV the helicalresistance strung upon said core In presence of and attached thereto soas to be insulated WM. H. BERRIGAN, In,

from the casing, and conductors connecting JAMES J. COSGROVE.

